Enables CONFIG_HARDENED_USERCOPY checks on ia64.
Based on code from PaX and grsecurity.
Signed-off-by: Kees Cook <keescook@chromium.org>
(cherry picked from commit 73d35887e24da77e8d1321b2e92bd9b9128e2fc2)
Signed-off-by: Alex Shi <alex.shi@linaro.org>